diff --git a/platform/source/mbed_semihost_api.c b/platform/source/mbed_semihost_api.c
index 2ee681b..7e059b4 100644
--- a/platform/source/mbed_semihost_api.c
+++ b/platform/source/mbed_semihost_api.c
@@ -121,8 +121,8 @@
     uint32_t args[4];
     args[0] = (uint32_t)old_name;
     args[1] = (uint32_t)strlen(old_name);
-    args[0] = (uint32_t)new_name;
-    args[1] = (uint32_t)strlen(new_name);
+    args[2] = (uint32_t)new_name;
+    args[3] = (uint32_t)strlen(new_name);
     return __semihost(SYS_RENAME, args);
 }
 #endif